ESTUDO DO COMPORTAMENTO DE VIGAS DE CONCRETO ARMADAS A FLEXÃO COM ARMADURAS NÃO-METÁLICAS DE GFRP

Abstract

This work is based on the replacement of conventional steel bars by GFRP (Glass Fiber Reinforced Polymer) bars for reinforced concrete structures. Concrete beams reinforced with steel bars were designed according to the ACI 318 (ACI, 2019) and concrete beams reinforced with GFRP bars by using ACI 440.1R (ACI, 2015), in order to study, comparatively, the load carrying capacity and the failure mode of the elements. Price quotations were made for the comparison of the execution costs of the beams. It was possible to conclude that, with equivalent reinforcement ratios, it was verified that the use of GFRP bars results in higher resistance capacities, ranging from 177 to 113% for the same cross-sections designed with conventional steel. When considering the same GFRP and steel bars diameters, beams reinforced with steel presented a 20% higher strength than the ones with GFRP bars. Concerning to the failure mode of the beams, the conventional steel bars yields, while the GFRP bars is based on the tensile bars rupture or on the concrete crushing. Finally, for short-term analysis, the costs of using GFRP reinforcing bars are higher than conventional steel bars. However, it is necessary to evaluate the maintenance costs of the structures, since the GFRP concrete reinforced beams are more resistant to environmental aggressive conditions and presents lower maintenance costs when taking into account the service life of the structures.